STILLING BY TAKING ADVANTAGE CUSTOMERS

I Use NOBLE.COM service for over a year and lately I noticed that the minutes received for the same value ($20) was lower than before (200min+).
Normally I call to purchase the airtime and the seller representative would confirm by phone how much I want to buy as well my Cr. Card information and even take the opportunity to perused me to buy more air time for a discount.
For my surprize, June 17, 2015 I bought air time for 200+ minutes at a value of $20 of which I made one call and when I went to make another call there was only 19 minutes left at a value of $4.
I call them, the seller representative was also surprised and after checking she tells me that the rates to the country where I was call went up and nothing they could do to adjust my minutes to what I was expecting, but she could compensate with a $5 Minutes due to the fact that I was not informed at the time of purchase, I rejected because I wanted my full minutes as expected.
She give me a number to call and talk to a supervisor, summarizing the supervisor give the same answer and added that I should constantly check their website for the rates change.
I said that I have used direct communication with them of which they had time and remembered to advertise their promotions and not to inform about the rates!
I don't recommend this service anymore to anybody and am cancelling all numbers and friends I have added do far.

I loss more than 150 minutes+ by this attitude of poor customer service.